1. Field Of The Invention
The present invention relates generally to tools for splitting earth, and more specifically to a wedge driven by hand and foot power.
2. Description Of The Related Art
A wide variety of construction and cultivating tasks require that a neat furrow be cut several inches into the earth. For example, shallow undersurface conduits such as sprinkler lines, and outdoor electrical wiring, need to be sufficiently buried for protection and to meet local building codes. Unfortunately, it is often difficult to cut a neat furrow, especially when compacted soils, dried clay, hard-pan and the like prevent conventional hand tools from penetrating sufficiently. For example, when a pick or grubbing hoe is swung against hard earth it tends either to bounce off or to penetrate only slightly. Repeated swings may force compacted earth to yield, although it is difficult to cut a precise furrow in this manner even in loose soils.
Shovels and spades of many designs may also be employed, although even when urged against the earth's surface with foot pressure, some soils continue not to yield. And, shovels and spades tend only to make a thin slice in the earth; to make a furrow of substantial width, they need to be rocked to and fro.
Various earth piercing devices ar found in the patent literature, one example of these being shown in U.S. Pat. No. 3,838,739 issued to Pollard in 1974. Pollrd's device includes a handle bar and a foot pressure bar, although it is adapted merely to punching smalll, circular holes in the earth. Another such device is shown in U.S. Pat. No. 1,323,630 issued to Hall in 1919, Hall's device having a loop-shaped handle. Hall employs a foot rest for pressure from a single foot and, like Pollard, punches small, circular holes. Unfortunately, it is cumbersom and inefficient to attempt to align circular holes to create a neat furrow.
U.S. Pat. No. 1,757,925 issued to Kirkpatrick in 1930 shows a device having interchangeable earth piercing tips. One of Kirkpatrick's tips is a cone for making circular holes, as above. The other is a blade shaped as a thin, rectangular wedge able to make a slice in the earth the length and thickness of the blade. However, in order to make a furrow of substantial width using the blade, the handle of Kirkpatrick's device must be rocked to and fro to widen the slice in the earth. Further, as Kirkpatrick's blade is narrower than his handle, the blade of his tool cannot be placed flush against the side of a solid object and driven directly downward. For example, if used close against the edge of a cement walk, the ridge above the blade will catch as the tool begins to sink into the earth.
Swedish Patent No. 128,874 shows a combination tool having a rake-like hoe at one end of an elongate handle and an earth piercing tip at the other. This device also includes a foot pressure bar adjacent its earth piercing tip. The tip is triangular in cross-section, and has its broadest face in the same plane as the surface of its handle, permitting work next to solid objects. However, when driven into the earth, the device of the Swedish Patent will merely punch triangular holes; it will not divide the earth such that repeated, laterally-aligned strokes create a neat furrow.
Thus, it appears that a need exists for a hand tool able to cut a neat furrow of substantial width, even in compacted soils. Further, it is desirable that the tool be useable up against solid bariers such as walls, and the like.